| 摘要 |
PURPOSE:To reduce power consumption, increase an operation speed, and improve the high-speed operation limit frequency of an output in terms of electric power and propagation time by varying load resistance with a low-voltage input signal level, and varying the current ability of a current source. CONSTITUTION:The level shifting circuit 4 consisting of a current control part 1 and a level shifting part 2 is used. Then, when a buffer input level VB rises up to a level H at a high speed, the short-circuit current flowing from and to the power source through a complementary type buffer transistor (TR) decreases. When the number of output terminals increases, the current consumed for current control is disregarded, so the current consumed by the level shifting circuit 4 is considered to be the same as usual, and the propagation time from the input of an output enable signal BK to DO output is shortened securely. Further, the short-circuit current of a buffer driver decreases, so the speed is increased in terms of current consumption and transmission time and the high-speed operation limit frequency of the output is improved in terms of electric power and transmission time. |
